• Journal of Korean Ophthalmic Optics Society
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• v.10 no.3
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• pp.247-253
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• 2005

We tried to design a Galilean telescopic spectacles for low vision which is with reference to goods of German. The design bases are that the magnification is 2.2X for general using and the diameter of aperture stop is 3mm. The Galilean telescopic spectacles is designed by using Sigma 2100 made in Kidger Optics Ltd. As a result, we have got the system that the MTF-value is more than 0.25 at 0.25 cycles/arc-minute and the distortion is under 1%. This system is judged to be useful for low vision.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.6 s.177
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• pp.1479-1490
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• 2000

The design process of the motor driven tilt/telescopic steering column is established by axiomatic design approach in conceptual design stage. By selecting independent design variables for improvin g performance of the steering system, each detailed design can be carried out independently. In the detailed design, the safety in crash environment and vibration reduction are considered. An occupant analysis code SAFE(Safety Analysis For occupant crash Environment) is utilized to simulate the body block test. Segments, contact ellipsoids and spring-damper elements are used to model the steering column in SAFE. The model is verified by the result of the body block test. After the model is validated, the energy absorbing components are designed using an orthogonal array. Occupant analyses are performed for the cases of the orthogonal array. Final design is determined for the minimum occupant injury. For vibrational analysis, a finite element model of the steering column is defined for the modal analysis. The model is validated by the vibration experiment. Size and shape variables are selected for the optimization process. An optimization is conducted to minimize the weight subjected to various constraints.

• The Journal of Advanced Prosthodontics
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• v.12 no.1
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• pp.38-48
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• 2020

PURPOSE. The objective of this literature review was to analyze the cumulative survival rates (CSRs) of rigid and non-rigid double-crown-retained removable dental prostheses. MATERIALS AND METHODS. Screening of the literature published from January 1995 to December 2019 was performed by using electronic data base (Pubmed) and manual search. The CSRs of rigid and non-rigid double crown removable dental prostheses were investigated. RESULTS. A total of 403 articles were reviewed and 56 relevant articles of them were selected. Subsequently, 25 articles were included for data extraction. These articles were classified according to rigid and non-rigid type double crowns and further subdivided into teeth, implants, and teeth-implant combination types. The CSRs of rigid type double crown ranged from 68.9% to 95.1% of 5 to 10 years in tooth abutments, 94.02% to 100% over a 3-year mean observation periods in implant abutments, and 81.8% to 97.6% in tooth-implant combination. Non-rigid type double crowns had various CSR ranges from 34% to 94% maximum during 10 years observation in teeth abutment. The CSRs of non-rigid type had over 98% in implant abutments, and ranged from 85% to 100% in tooth-implant combination. CONCLUSION. The CSRs of double crowns varies according to types. With accurate evaluation of the remaining teeth and plan of the strategic implant placement, it could be successful treatment alternatives for partially or completely edentulous patients.

• 대한치과보철학회:학술대회논문집
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• 1994.05a
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• pp.19-19
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• 1994

• 대한치과보철학회:학술대회논문집
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• 1999.11a
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• pp.73-73
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• 1999

• 대한치과보철학회:학술대회논문집
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• 2002.11a
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• pp.35-35
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• 2002

• 대한치과보철학회:학술대회논문집
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• 2001.04a
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• pp.40-40
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• 2001

• 대한치과보철학회:학술대회논문집
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• 2000.04a
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• pp.61-61
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• 2000

• 대한치과보철학회:학술대회논문집
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• 2000.04a
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• pp.62-62
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• 2000

• 대한치과보철학회:학술대회논문집
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• 2002.04a
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• pp.51-51
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• 2002